import gov.nasa.jpf.ListenerAdapter;
import gov.nasa.jpf.vm.VM;
import gov.nasa.jpf.vm.VMListener;

public class Garbage extends ListenerAdapter implements VMListener 
{
	private long start;
	
	public void gcBegin(VM vm) 
	{
		this.start = System.currentTimeMillis();
	}
	
	public void gcEnd(VM vm) 
	{
		System.out.println(System.currentTimeMillis() - this.start);
	}
}